In contrast, tumors arising in IL6-/-;Eμ-myc mice were markedly biased toward a more mature IgM+ B cell phenotype and were composed of large atypical lymphoid cells with large nuclei, resembling human diffuse large B cell lymphoma [DLBCL] [Figs 1F and S1D]. This evidence concerns the gene CD40LG and diffuse large B-cell lymphoma.